Biomedical Devices and Instrumentation Commons^™

Noncontact Diffuse Correlation Tomography Of Breast Tumor, Lian He

Theses and Dissertations--Biomedical Engineering

Since aggressive cancers are frequently hypermetabolic with angiogenic vessels, quantification of blood flow (BF) can be vital for cancer diagnosis. Our laboratory has developed a noncontact diffuse correlation tomography (ncDCT) system for 3-D imaging of BF distribution in deep tissues (up to centimeters). The ncDCT system employs two sets of optical lenses to project source and detector fibers respectively onto the tissue surface, and applies finite element framework to model light transportation in complex tissue geometries. This thesis reports our first step to adapt the ncDCT system for 3-D imaging of BF contrasts in human breast tumors. A commercial 3-D …

Diffuse Optical Measurements Of Head And Neck Tumor Hemodynamics For Early Prediction Of Chemo-Radiation Therapy Outcomes, Lixin Dong

Theses and Dissertations--Biomedical Engineering

Chemo-radiation therapy is a principal modality for the treatment of head and neck cancers, and its efficacy depends on the interaction of tumor oxygen with free radicals. In this study, we adopted a novel hybrid diffuse optical instrument combining a commercial frequency-domain tissue oximeter (Imagent) and a custom-made diffuse correlation spectroscopy (DCS) flowmeter, which allowed for simultaneous measurements of tumor blood flow and blood oxygenation. Using this hybrid instrument we continually measured tumor hemodynamic responses to chemo-radiation therapy over the treatment period of 7 weeks. We also explored monitoring dynamic tumor hemodynamic changes during radiation delivery. Blood flow data analysis …

Nasa Limited Inflight Lab Sensor, Gregory P. Howard, James C. Hanreck

Williams Honors College, Honors Research Projects

The National Aeronautics and Space Administration (NASA) is currently developing the capabilities needed to send humans to Mars in 2030 for a three year mission. Astronaut health must be monitored monthly during such a lengthy mission. The UA Enterprise Senior Design Team worked to design a reusable, novel blood panel cartridge system to monitor astronaut health and to minimize waste production. Most current cartridges are composed of polydimethylsiloxane (PDMS). PDMS microchannels were fabricated to conduct simple proof of concept experiments for the design of a novel cartridge. To determine an ideal blood cleaning solution, bovine blood will be injected into …

Foley Catheter Priming Device, Melissa A. Boswell, Landon Davis, Renee Horn, Tyler Grubb, Jason Green

Williams Honors College, Honors Research Projects

A lack of a pressure gradient throughout the catheter prevents urine flow from the bladder and through catheter system in a condition referred to as “air-lock.” The purpose of this project was to design a device that could be utilized by person with a catheter faced with the problem of air-lock to restore urine flow and normal functioning of the catheter system. After a prototype was created, the device was put through a series of tests to insure proper functioning, absence of leakage, and durability. The device created can be added in-line with the catheter system, inconspicuously under the user’s …

Effect Of Nitrogen On Properties Of Na2o-Cao-Sro-Zno-Sio2 Glasses, Ahmed Bachar, Cyrille Mercier, Arnaud Tricoteaux, Jean Christophe Hornez, Anne Leriche, Claudine Follet, Bertrand Revel, Stuart Hampshire, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

Glasses in the Na₂O-CaO-SrO-ZnO-SiO₂ system have previously been investigated for suitability as a reagent in Al-free glass polyalkenoate cements (GPCs). These materials have many properties that offer potential in orthopedics. However, their applicability has been limited, to date, because of their poor strength. This study was undertaken with the aim of increasing the mechanical properties of a series of these Zn-based GPC glasses by doping with nitrogen to give overall compositions of: 10Na₂O-10CaO-20SrO-20ZnO-(40-3x)SiO₂-xSi₃N₄ (x is the no. of moles of Si₃N₄). The density, glass-transition temperature, hardness, …

Peracetic Acid: A Practical Agent For Sterilizing Heat-Labile Polymeric Tissue-Engineering Scaffolds, William R. Trahan

Theses and Dissertations

Advanced biomaterials and sophisticated processing technologies aim to fabricate tissue-engineering scaffolds that can predictably interact within a biological environment at a cellular level. Sterilization of such scaffolds is at the core of patient safety and is an important regulatory issue that needs to be addressed prior to clinical translation. In addition, it is crucial that meticulously engineered micro- and nano- structures are preserved after sterilization. Conventional sterilization methods involving heat, steam and radiation are not compatible with engineered polymeric systems because of scaffold degradation and loss of architecture. Using electrospun scaffolds made from polycaprolactone (PCL), a low melting polymer, and …

Design And Creation Of A Device To Induce Vergence Eye Movements, Jacob B. Jaminet, Paul A. Wetzel

UROP Posters

Automated eye-tracking systems can detect and analyze eye movements as a means to accurately diagnose more than 20 neurological diseases including mild traumatic brain injury. Mild traumatic brain injury is an occurrence of injury to the head resulting from blunt trauma or from acceleration or deceleration forces. Eye movement refers to the voluntary or involuntary movement of the eyes, helping in acquiring, fixating and tracking visual stimuli. There are three types of voluntary eye movement to track objects: smooth pursuit, vergence shifts and saccades. Vergence shifts are eye movements where the eyes move in opposite directions: moving to the midline …

Shotblocker® - Bionix® Senior Design, Samuel Dockery

Williams Honors College, Honors Research Projects

No abstract provided.

Assessment Of Electrode Configurations Of Electrical Impedance Myography For The Evaluation Of Neuromuscular Diseases, Khondokar Mohammad Fazle Rabbi

College of Graduate Studies: Theses & Dissertations

Electrical impedance myography (EIM) is a painless, noninvasive approach to measure the neuromuscular disease status. EIM parameters- resistance (R), reactance (X) and phase (θ) depend significantly on subcutaneous fat thickness, muscle size and inter electrode distance. The objective of this research is to find an electrode configuration which can minimize the effects on EIM parameters due to subcutaneous fat thickness variation. In this study, a model of human upper arm was developed using finite element method (FEM), which has already been established as an appropriate approach for the analysis of non-symmetrical shape for assessing alternations of muscle in disease-induced changes …

Biocorrosion Rate And Mechanism Of Metallic Magnesium In Model Arterial Environments, Patrick Bowen

Dissertations, Master's Theses and Master's Reports

A new paradigm in biomedical engineering calls for biologically active implants that are absorbed by the body over time. One popular application for this concept is in the engineering of endovascular stents that are delivered concurrently with balloon angioplasty. These devices enable the injured vessels to remain patent during healing, but are not needed for more than a few months after the procedure. Early studies of iron- and magnesium-based stents have concluded that magnesium is a potentially suitable base material for such a device; alloys can achieve acceptable mechanical properties and do not seem to harm the artery during degradation. …

Monolithic Optofluidic Ring Resonator Lasers Created By Femtosecond Laser Nanofabrication, Hengky Chandrahalim, Qiushu Chen, Ali A. Said, Mark Dugan, Xudong Fan

Faculty Publications

We designed, fabricated, and characterized a monolithically integrated optofluidic ring resonator laser that is mechanically, thermally, and chemically robust. The entire device, including the ring resonator channel and sample delivery microfluidics, was created in a block of fused-silica glass using a 3-dimensional femtosecond laser writing process. The gain medium, composed of Rhodamine 6G (R6G) dissolved in quinoline, was flowed through the ring resonator. Lasing was achieved at a pump threshold of approximately 15 μJ/mm². Detailed analysis shows that the Q-factor of the optofluidic ring resonator is 3.3 × 10⁴, which is limited by both solvent …

Neural Network Based Emg Driven Modeling And Control Of Human Walking, Alaa Muheddin Abdulrahman

Theses and Dissertations

Human body modeling (HBM) offers the benefit of replicating human activity into robotics and rehabilitation devices. Gait impairment is a consequence of several diseases like stroke, spinal cord injury, or Parkinson' disease. The modeling techniques developed in robotics have been used to improve gait abnormalities in walking and in building Exoskeletal robots. HBM is resource intensive as it requires setting-up laboratory facilities and using expensive instruments. Further, the data acquired is limited to the number of the participants. In addition, the accuracy of the model is important as it is related to human pathology. In this research, several Matlab based …

Processing And Mechanical Testing Of Strontium-Substituted Hydroxyapatite/Glass Composites, Chokchai Yatongchai, Mark R. Towler, Anthony W. Wren

Chemical and Biochemical Engineering Faculty Research & Creative Works

Sr-HA/Glass composites were produced. Phase composition of composites was evaluated. Their physical and mechanical properties were determined. Sintered composites mainly consisted of Sr-HA/β-TCP, or β-TCP/Ca₂ZnSi₂O₇. The composites had porosity up to 4 times those of undoped Sr-HA. Compared to undoped Sr-HA, the Sr-HA/Glass composites had lower biaxial flexural strength and hardness. The Weibull modulus for the composites ranged from 2.77 to 18.74.

Development Of A Novel Device For The Perfusion Driven Decellularization Of Skeletal Muscle, Benjamin Kasukonis

Graduate Theses and Dissertations

Decellularization of skeletal muscle is a process that removes cellular components of skeletal muscle tissue while leaving behind the intact extracellular matrix (ECM). Skeletal muscle ECM is currently being studied as a biologic scaffold for repairing volumetric muscle loss (VML) because the removal of cells greatly reduces the antigenicity of the donor tissue. Decellularization usually relies on passive diffusion of detergents, surfactants and/or osmotic solutions to strip cells from the ECM. However, passive diffusion alone is usually not sufficient for complete removal of cells from the interior of large pieces of skeletal muscle using detergents, such as sodium dodecyl sulfate …

Induction Of Differentiation Of Dental Pulp-Derived Mesenchymal Stem Cells (Dpsc), Aubrey Young

UNLV Theses, Dissertations, Professional Papers, and Capstones

Mesenchymal stem cells are derived from a variety of human tissues and are being bioengineered and studied for possible uses in the advancement of medicine. Recent efforts are being focused on Dental Pulp Stem Cells (DPSC's) due to the accessibility of this tissue. Many factors influence DPSC quality and quantity, including the specific methods used to isolate, collect, concentrate, and store these isolates once they are removed. Ancillary factors, such as the choice of media, the selection of early versus late passage cells, and cryopreservation techniques may also influence the differentiation potential and proliferative capacity of DPSC isolates.

The objective …

A Portable Impedance Biosensing System Based On A Laptop With Labview For Rapid Detection Of Avian Influenza Virus, Yixiang Wang

Graduate Theses and Dissertations

Avian Influenza Virus (AIV) H5N1 is a highly pathogenic virus found not only in birds but also in human. Rapid and sensitive detection method is needed to help prevent the spread of AIV H5N1. In this study, a portable impedance biosensing system based on a laptop with LabVIEW software was developed for detection of AIV H5N1. First, a virtual instrument was programmed with LabVIEW software to form a platform for impedance measurement, data processing and control. The audio card of a laptop was used as a function generator while a data acquisition card was used with the signal channels for …

Designing A Biomimetic Testing Platform For Actuators In A Series-Elastic Co-Contraction System, Ryan Tyler Schroeder

UNLV Theses, Dissertations, Professional Papers, and Capstones

Actuators determine the performance of robotic systems at the most intimate of levels. As a result, much work has been done to assess the performance of different actuator systems. However, biomimetics has not previously been utilized as a pretext for tuning a series elastic actuator system with the purpose of designing an empirical testing platform. Thus, an artificial muscle tendon system has been developed in order to assess the performance of two distinct actuator types: (1) direct current electromagnetic motors and (2) ultrasonic rotary piezoelectric motors. Because the design of the system takes advantage of biomimetic operating principles such as …

Development Of A Heart Rate Variability Measurement System Using Embedded Electronics, Naresh Kumar Velmurugan

Graduate Theses and Dissertations

Recent advances in embedded electronics have a remarkable influence on the health care system. One of the most important applications is to monitor the health care of the patients at anytime and anyplace. In the last two decades, many researchers have focused mainly on heart rate variability (HRV) measurements. Patient's heart rate variability should be continuously monitored to help them in case of emergency. Under these circumstances, patients are required to have a HRV measuring kit for a constant observation.

The proposed project focuses on the development of a heart rate variability measurement system with the use of embedded electronics. …

Wear Resistant And Biocompatible Coatings For Medical Devices And Method Of Fabrication, Mary Gilliam, Susan Farhat, Ali Zand

Chemical Engineering Patents

Abstract: A method of forming a biocompatible or biologically inert article for use in an application in which the article will make contact with at least one tissue, organ, or fluid within a human or animal body is provided. The method generally comprises providing an article having an external sur face; selecting chemical precursors; using a means to direct one or more chemical precursors towards or to apply such chemical precursors to the ex ternal surface; activating the chemical precursors by exposing said precursors to atmospheric pressure plasma; and grafting and/or cross-linking the chem ical precursors to form a solid …

Applications Of Novel Mri Technologies In Tissue Engineering And Disease Diagnosis, Vahid Khalilzad-Sharghi

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Magnetic resonance imaging (MRI) and magnetic resonance elastography (MRE) are increasingly under investigation to explore their potential role in establishing effective evaluation methods for the procedure of tissue regeneration carried out in vitro, in vivo, and in disease diagnosis. To this end, there is a continuous pursuit of novel tools both in vitro and in vivo. For instance, there is a great need for the development and evaluation of an MR-compatible incubation system that enables simultaneous monitoring and culturing of cell and tissue constructs using MRI techniques. Such an imagingcompatible incubation system eliminates exposing the culture to the risks of …